This year marks the centennial of America's first transcontinental road: the Lincoln Highway. You might have driven on the highway and not even known it, since it stretches from New York to California, passing through states like Iowa, Nebraska and Colorado, and carrying different state route numbers along the way.

Saying that "it's time to question laws that senselessly expand the concept of self-defense and sow dangerous conflict in our neighborhoods," Attorney Gen. Eric Holder on Tuesday called for a reexamination of so-called stand your ground laws.